The Diabetic 87-year-old who's 63 and not diabetic.

"Doc, we didn't see you yesterday."

"Yeah, I was off yesterday.  But someone should have stopped by -- there's always a doctor covering."

"Someone did, but we didn't like him."

"Why not?"

"He came in and thought our mother was 87 and diabetic."

"He must have had the wrong chart."

"No, he said that was in the chart.  He showed us."

"She's never been diabetic, right?"

"No."

"That's weird.  I don't know how that happened, but I'll check the chart and fix any mistakes I see."

"Also... you don't think she looks 87, do you?"

"Of course not... but it's hard to judge people's age when they're sick.  Everyone looks older than they really are."

"So how old do you think she looks?"

"That's not a fair question, because I know she's 63."

"But if you didn't know."

"I'd say she looks like an ill 63 year old, unfortunately."

"She used to look 40."

"She used to be 40."

"But you're sure she doesn't look 87."

"Yes."

"Good, because then there's no biological way I could be her son."